Theresa May in new clash with Bank of England Governor Mark Carney over Brexit uncertainty

Prime Minister Theresa May (AFP/Getty)

Hostilities between Theresa May and Mark Carney have reignited after Downing Street rejected the Bank of England Governor’s call for greater "clarity" over the UK’s approach to Brexit.

Number 10 dismissed Mr Carney’s call on Wednesday to give Britain’s businesses greater certainty on Ms May’s negotiating position, as akin to "showing all the cards at the outset" of Brexit talks.

Downing Street has already fallen out with Mr Carney over the effectiveness of monetary policy, while it was recently claimed the Bank chief is working on a ‘secret plan’ for a transitional deal which would see Britain stay in the EU’s single market until 2021, contrary to the goals of many Brexiteers.

After hearing about Mr Carney’s comments, a Downing Street spokesperson said: "What matters most for British business is that we get the best possible outcome in negotiations as we leave the European Union."

They spokesperson added: "That doesn’t mean showing all the cards at the outset."

Asked about relations between No 10 and the Governor, the spokesperson said they were "as good as they have ever been".

Mr Carney said earlier in the day that it would be preferable for business to know as much as possible about the "desired endpoint" of Ms May’s plans. He added: "Having a degree of clarity, when appropriate, will help promote a smooth and orderly transition."

It follows reports that the Governor has held private meetings and dinners in the past two weeks, appealing to business leaders to focus on a common goal for Britain’s EU exit.

His reported plan, dubbed the "Brexit buffer", would mean companies operating under the current trading rules, almost certainly including freedom of movement for EU citizens, until 2021 when they have properly prepared for a transition.

Mr Carney set himself on a collision course with Ms May after rebuffing economic claims made in her keynote Conservative conference speech.

He argued that the monetary policy pursued by the Bank in recent years has had a positive impact that is "without parallel", despite the Prime Minister using her speech to claim it had led to "bad side effects".